82 



BIOLOGY OF THE PROTOZOA 



nuclei during stages of division (Fig. 40) . Similar pole plates appear 

 as broad, flat, and hyaline ends of the spindles of Adinosphoerium 

 eichhomii according to Hertwig (1898), in the spindle of Tricho- 

 sphcErium slehoJdi according to Schaudinn (1899), and in the macro- 

 nucleus of Spirochona geinmipara (Hertwig). In this group, also, 

 we would include the peculiar hyaline globular bodies at the poles 









imn 





''%^0^ 





Fig. 39. — Arnoeba vespertilio Dof. Origin of the .spindle within the nucleus (1,2), 

 nuclear division (5, 6, 7), and reconstruction of nuclei after division (3, 4, 8, 9), 

 (After Doflein.) 



of the nuclear spindles of Euglypha aJveoIaia as described by 

 Schewiakoff (1888). 



It is quite possible, although direct evidence is lacking, that none 

 of these peculiar pole plate structures belongs to the group of 

 kinetic elements. Indirect evidence favoring this possibility is 

 furnished by the entire absence of observations on the division of a 



